Beta

×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

Comments

top

23-Year-Old Chess Grandmaster Whips Bill Gates In 71 Seconds

Old Wolf Re:71 vs 79 seconds (449 comments)

Carlsen didn't seem entirely sure that it had started

This is normal: when you start the clock, there is no visual indicator until 1 second has passed, and the time ticks down to the next second. So there is that short period where you aren't sure if your press registered or not.

about 6 months ago
top

23-Year-Old Chess Grandmaster Whips Bill Gates In 71 Seconds

Old Wolf Re:71 vs 79 seconds (449 comments)

Gates made his move without starting the clock and then they sat around chatting for a while before Magnus started the clock.

about 6 months ago
top

23-Year-Old Chess Grandmaster Whips Bill Gates In 71 Seconds

Old Wolf Re:Big deal. (449 comments)

It's wrong then, those times were for the whole game. If you watch the video of the match, this is clear.

about 6 months ago
top

23-Year-Old Chess Grandmaster Whips Bill Gates In 71 Seconds

Old Wolf Re:Big deal. (449 comments)

If you actually watch the video, they were playing a timed game. The World Champion (funny how the slashdot title omits that minor detail??) had 30 seconds, Bill had 2 minutes.

about 6 months ago
top

23-Year-Old Chess Grandmaster Whips Bill Gates In 71 Seconds

Old Wolf Re:Bill (449 comments)

At least he knows how to play minesweeper. (A reddit thread recently revealed that a lot of people had been playing it by randomly clicking, and either ignored the numbers, or thought they were points).

about 6 months ago
top

Brain Function "Boosted For Days After Reading a Novel"

Old Wolf So it is true (110 comments)

‘A reader lives a thousand lives before he dies, said Jojen. The man who never reads lives only one.’

about 7 months ago
top

Enormous Tunneling Machine 'Bertha' Blocked By 'The Object'

Old Wolf What's with (339 comments)

all the boring stories lately?

about 7 months ago
top

How Your Compiler Can Compromise Application Security

Old Wolf Re:The paper gives examples (470 comments)

While this check appears to work on a flat address space, it fails on a segmented architecture.

It may not even work on a flat address space, if "buf"'s allocated block is right at the end of the addressable space.

about 9 months ago
top

How Your Compiler Can Compromise Application Security

Old Wolf Re:TFA does a poor job of defining what's happenin (470 comments)

I think you must be mis-remembering the details slightly. The comma operator is a sequence-point, so "tmp" must be assigned the value of "a", and f() and g() must both be called with a value that is the value of "a" converted to the type of "tmp". The two functions can be called in either order though (or in parallel) but there is no issue there.

Of course, the compiler can do anything it likes so long as the program's output is equivalent to what I just described. So, for example, it might not allocate a memory location to "tmp", it could just push the value of "a" onto a register and then call f and g with it. Or if f or g do nothing and have no side-effects, the assembly code might not show calls to f and g. But there is no way you could know these things by running the program, which is the whole point.

about 9 months ago
top

How Your Compiler Can Compromise Application Security

Old Wolf Re:TFA does a poor job of defining what's happenin (470 comments)

"Overflows of unsigned values" is NOT undefined. You can assign out-of-range values to unsigned types, and also perform arithmetic operations which exceed the bounds of the type; and the value is adjusted using modular arithmetic.

Some would be facetious and say that "unsigned types cannot overflow", meaning that they always have well-defined behaviour on operations that would generate an out-of-range value, but that's just an issue of pedantry with English.

about 9 months ago
top

How Your Compiler Can Compromise Application Security

Old Wolf Re:TFA does a poor job of defining what's happenin (470 comments)

>The dereference is undefined, and therefore

Stop right here. Once undefined behaviour occurs, "all bets are off" as they say; the remaining code may have any behaviour whatsoever. C works like this on purpose , and it's something I agree with. It means the compiler doesn't have to insert screeds of extra checks , both at compile-time and run-time.

There are plenty of other languages you can use if you want a different language definition :)

about 9 months ago
top

How Your Compiler Can Compromise Application Security

Old Wolf Re:TFA does a poor job of defining what's happenin (470 comments)

>a == b is not a use of the argument that has been invalidated

Yes it is. Evaluating the expression "a" causes undefined behaviour if "a" is
indeterminate. "a" is considered to no longer have a value, any attempt to
refer to its value causes UB. (It has the same status as a variable that has
been defined but not initialized, i.e. "int a;"

The only thing that can be done with "a" thereafter is to assign a new value to it
(or take its address, or do "sizeof a" .. can't think of any other exceptions)

about 9 months ago
top

How Your Compiler Can Compromise Application Security

Old Wolf Re:TFA does a poor job of defining what's happenin (470 comments)

>If my C code contains *foo=2, the compiler can't just leave that out

Well, it could if the program produces no further output before exiting, or if "foo" is unassigned.

about 9 months ago
top

"Ballooning" Spiders Use Electrostatic Forces To Generate Lift

Old Wolf Re:hmm (213 comments)

What if you hold a metal rod up though, that would have a lower resistance.

about 10 months ago
top

Reddit Bans Subreddit Dedicated To Finding Navy Yard Shooters

Old Wolf This isn't even news (159 comments)

All that happens on such a subreddit is wild speculation. Last time they did it, innocent people wrongly identified got harrassed IRL. They're not detectives. Just send any real tips direct to the FBI.

about 10 months ago
top

Toronto Family Bans All Technology In Their Home Made After 1986

Old Wolf Paper maps (534 comments)

...it's not normal to travel with paper maps?

about 10 months ago
top

Feds Seek Prison For Man Who Taught How To Beat a Polygraph

Old Wolf Re:It's more like a cliff! (374 comments)

Yeah and how is he going to do that?

We can't all hole up in a Moscow airport.

about 10 months ago
top

Feds Seek Prison For Man Who Taught How To Beat a Polygraph

Old Wolf Re:Legal slippery slope (374 comments)

Why is it bad to teach people to avoid a polygraph, when polygraphs aren't admissible as evidence in court anyway?

Next thing you know they'll be banning books on body language.

Then books on English. The war with Eastasia will probably be used as justification.

about 10 months ago

Submissions

top

LHC finds 3.5-sigma CP violation in Charm Meson

Old Wolf Old Wolf writes  |  more than 2 years ago

Old Wolf (56093) writes "On Monday in Paris, members of the LHCb collaboration presented a 3.5 sigma observation of an unexpected CP violation in the decay of the D0, a particle made up of a charm quark and an up antiquark. TheStandard Model predicts this particular decay has a CP-violating asymmetry close to zero, yet LHCb observed a much larger value of -0.82 percent.

Here's a more technical writeup, as well as the actual presentation."

Link to Original Source
top

All Languages Linked to Common Source

Old Wolf Old Wolf writes  |  more than 3 years ago

Old Wolf (56093) writes "A New Zealand evolutionary psychologist, Quentin Atkinson, has created a scientific sensation by claiming to have discovered the mother of all mother tongues. By studying the sounds made in 504 modern languages, Atkinson said he had found an ancient signal in them."
Link to Original Source

Journals

Old Wolf has no journal entries.

Slashdot Login

Need an Account?

Forgot your password?
or Connect with...

Don't worry, we never post anything without your permission.

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>